1. Field of the Invention
The present invention is directed to electrical power distribution devices; particularly load bases which provide electrical connection between a fuse and an electrical cable that is connected to a load.
2. Description of Art
Electrical distribution devices often utilize fuses for circuit protection devices. Load bases, sometimes also referred to as fuse blocks, are used to provide electrical continuity from an electrical cable to the fuse. In some applications, a load base is used on each end of a fuse, i.e., on both the so-called load and line ends of the fuse. In other applications, a disconnect switch is used on the line end of the fuse and a load base is used on the load end of the fuse, i.e., the end closer to the device which utilizes electrical power.
Known fuse bases and fusible switches generally have an insulating base and a conductive bus attached to the base which has threaded apertures for attachment of a wire lug with a threaded member, such as a machine screw. A load base has a fuse clip attached to the conductive strip and electrical continuity is established between a wire connected to a load and a fuse by connection of the wire to the wire lug and insertion of a fuse conductive end into the fuse clip. Fusible switches often have a line end similar to a load base and a set of stationary switch terminals, attached to the conductive bus in lieu of a fuse clip. The switch has a translatable blade contact assembly for completion of continuity with the stationary switch terminals and a fuse clip is electrically connected to the blade contact assembly. Examples of load bases and fusible switches are shown in U.S. Pat. Nos. 3,293,392; 3,525,835; 3,840,717; 3,993,395; 4,288,138 and 4,302,643.
Known load bases and fusible switches require attachment of the conductive bus to the insulating base with fasteners or by molding the conductive bus into the base. Some types of load bases and switches utilize fasteners for the dual purpose of mounting a lug or fuse clip to the conductive bus and in turn retaining the bus on the base. Removal of one of the fasteners causes disassembly of the components from the base that are secured by that fastener, and the components can be lost during field service.
Also, the requirement for a manufacturing facility to stock and install during assembly separate fasteners for retaining the lug to the conductive bus, the fuse clip to the conductive bus and the conductive bus to the base increases manufacturing costs.
It is an object of the present invention to create a wire lug which allows direct attachment of a fuse clip thereto without the need for an additional conductive bus strip or other like components.
It is another object of the present invention to minimize the number of components needed to establish electrical continuity between an electrical wire and a conductive end of a fuse, to minimize parts, inventory and manufacturing costs, assembly effort and discontinuities which may be caused by inadvertent component separation.
It is an additional object of the present invention to create a wire lug retainer which holds a wire lug in position relative to a load base or disconnect switch housing after removal of a fuse clip coupled to the lug.